Grass seed is sown by various known procedures. These procedures include hand seeding, “hydro-seeding” and using mats that form artificial seedbeds. Hand seeding is an old and well-known way of applying grass seed to the soil. According to the hydro-seeding method, grass seeds are mixed in a dissolved fiber solution and are dispersed on the surface of the ground. In the methods that employ a mat as an artificial seedbed, the mat is placed on top of the soil in order to grow and keep germinated grass warm and moist.
Many forms of artificial seedbeds, including seed mats and carpets, intended for growing grass and other forms of vegetation are known in the art. A conventional such seed mat is disclosed in U.S. Pat. No. 4,190,981 to Muldner. This conventional seed mat includes a base layer of water pervious web material, a bed of seeds and compressed peat particles as a middle layer, and an upper layer comprising a fibrous, porous veil. However, this upper layer does not have sufficient wet strength to support and position the seeds after watering commences. Also, the upper layer can prematurely degrade, thereby exposing and failing to protect young seedlings from other elements and birds.
It is therefore an object of the present invention to provide an improved artificial seedbed, in effect, an engineered seedbed with predetermined physical properties that enhances safe sprouting and growth of young vegetation. It is also an object of the present invention that provides an artificial seed bed with a lower layer that will be porous enough to allow roots to extend through it, but yet strong enough to support the seeds and retain some of the temperature and humidity of the soil around the seeds during seed germination and growth. It is a further object of this invention to provide an artificial seedbed with an upper layer that has a density and porosity that allows extensive sprouting of the shoots from the seed, while still being strong enough to protect these sprouting shoots from their environment.